Tire tread wear indicator



FIG. 1 is a fragmentary perspective view of a tire tread wear indicator showing our new design;

FIG. 2 is an enlarged fragmentary perspective view from the circled area shown in FIG. 1;

FIG. 3 is an enlarged partial front elevational view thereof from the circled area shown in FIG. 1; and,

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 3.

In the drawings, the broken lines showing of a tire depict environmental subject matter and form no part of the claimed design. 

CLAIM The ornamental design for a tire tread wear indicator, as shown and described. 